Spraying apparatus



July 28, 1942. J. A. 'rlscoRNlA SPRAYING APPARATUS I 2 Sheets-Sheet 1 Filed March 16, 1939 JNVENToR. JqMfs A. T/S Coe/vm ATTORNEY July 28, -1942. J. A. 'rlscoRNlA 2,291,423

sPRAYING- APPARATUS File'd March 16, 1939 2 Sheets-Sheet 2 ATTORNEY Patented July `28, 1942 2,291,423 sPaAYING APPARATUS' James A. Tiscornla, San Jose, Calif., assignor to Electro-Spray Corporation,

San Francisco,

Calif., a corporation of California Application March 16, 1939, Serial No. 262,207

8 Claims. (Cl. 299-87) The present invention relates to spraying apparatus, and more particularly to spraying apparatus of the type operating on a ilash boiler system. Such apparatus iinds advantageous use in the spraying of insecticides, germicides,- deodorants, or any type of atomizable liquid for various purposes;

This application is a continuation in part of my pending application Serial No. 60,306, filed January 22, 1936, for Sprayers.

A flash boiler is a steam chamber in which steam may be instantly generated in required quantity and substantially instantaneously. Such a flash boiler principle is disclosed in connection with a spraying apparatus in my Patent No. 1,999,265, dated April 30, 1935.

It is one object of the invention to provide sprayer apparatus of the character indicated, wherein steam generated in a ash boiler is used as the. means or vehicle which provides a force to atomize liquids discharged from an aspirator or spray nozzle.

Another object of the invention is to provide a device of the character indicated in which the steam is electrically or otherwise generated, and in which the steam chamber may be maintained at a substantially uniform temperature at all times when the device is connected to a source of electrical supply for instantly creating steam in the chamber.

Another object of the invention is to provide a device in which a liquid injector, steam generator, and steam-actuated aspirator unit are operatively combined in a small, compact and easily handled portable structure.

A further object is to provide a device including means whereby the steam forming liquid may be injected into the steam chamber in predetermined relatively small quantities as desired.

It is a still further object to provide a flash boiler system for spraying liquids and provide for safe and positive control of means to heat a flash boiler, including convenient and accessible control of vthe entry into a ilash boiler of a liquid from which steam may be generated.

With. the foregoing and other objects in view, all 'of which will be more apparent as this description proceeds, the invention is exemplified in the novel construction and combination of parts hereinafter described, illustrated in the accompanying drawings, and pointed out in the claims hereto appended, it being understood that various changes in the form, proportion, size and details to within the scope of the appended claims without departing from the spirit or sacrificing any of the advantages of the invention.

To more clearly comprehend the invention,`

reference is directed to the accompanying drawings wherein:

Fig. l is a side elevation of a device embodying my invention, partly in section and having parts broken away.

of construction of the apparatus may be resorted Fig. 2 is a transverse sectional view through a portion of another embodiment of the invention.

Fig. 3 is a transverse sectional view through still another embodiment of the invention.

Fig. 4 is a side elevation of a structure showing another embodiment of the invention.

Fig. 5 is a longitudinal verticalesection showing a modified form of the convenient portable apparatus of the invention.

Fig. 6 is a schematic illustration of a modified form which the invention may take for purposes of large scale operations.

Referring to the drawings of the present disclosure, I is a double wall cylinder denlng a steam chamber 2, both ends of the chamber being closed. One end of the cylinder is likewise closed by a wall t. Lining the inside of the cylinder I is a sheet of electrically insulating material such as isinglass or mica indicated 4. Removably inserted within the lines of cylinder I is a heater unit 5 comprising a cylinder of insulating material 5B and heating coils 5b in circumferential grooves 5, the heating coils being connected by suitable electrical conductors 6 and 'l to a source of electrical supply i, through a thermostat hereinafter described.

At 9 is a cap closure member seated in the open end of cylinder I to close the same and position and retain the heater unit. The cylinder I and the cap member 9 are covered with heat insulat ing material as at iii and II respectively.

At I2 is shown a tube communicating with the steam chamber 2 and fitted with a spray nozzle I3, the tube l2 having a receptacle cap I4 mounted thereon. 0n the cap I4 is mounted a tube I5 communicating with the tube I2 through a passage IS and extending downwardlyto a point adjacent the bottom of a receptacle Il seated in cap I6 as shown. The parts I2 to I'I form an aspirating device actuated by steam generated in chamber 2.

A receptacle for water is shown at I8, and this receptacle is fitted with a cap I9 provided with a handle 20. Mounted in, and extending through cap I9, is a tube 2l, one end of this tube communicating with the steam chamber 2 as at 22,

and the other end carrying a pump cylinder 23 disposed adjacent the bottom of the receptacle Il. In the cylinder 23 is mounted a piston 24 having passages 25 formed therein controlled by flap-valves 22. I'he piston 24 is operated by l means of a stem 21 passing upwardly through cap I9 and fitted with a head 23. A force means selectively operable manually is provided for pumping a small supply of fluid from cylinder 23 to the boiler chamber 2, in which a lever 29 is fulcrumed on cap I9 as at 30 and engages the under side of head 29 whereby the piston 24 may be raised by manual operation of the lever 29. The piston is normally maintained in a lowered position by a spring 3| inserted between the cap I9 and a stop member 32 on stem 21.

The tube 2| is provided with an enlarged portion 33 upon which a thermostat 34 is mounted. The part 34 of the thermostat is a bar of thermostatic bimetal insulated as at 35 from the end 29 to which conductor l is connected, and which contacts terminal 31 insulated at 38 and from which conductor 4 continues to source 3.

' When the device is to be used the receptacle I1 is filled with the material to be sprayed, the receptacle I9 is lled with water, and the electrical connections are connected into a source of electrical supply. When so connected the heater unit becomes active, thereby heating the chamber 2. There being a continuous metallic connection from the chamber 2 through its metallic walls I and tube 2| back to thermostat 34, it follows that when a given temperature is reached the thermostat will be operated to break the cir- J cuit, and upon a lowering of the temperature the circuit will again be closed, thereby maintaining a substantially uniform temperature in the chamber 2.

It will be noted that the volume of the pump cylinder 23 is relatively small compared with the volume of the fluid receptacle' I8, and that the upper surface area of piston 24 is large as compared with the interior passage of tube 2|, so that upon the forward or upward stroke of the piston a selective amount of fluid in the pump cylinder is supplied to the flash boiler chamber 2 in relatively small quantity at any one instant, as compared to the total volume capacity of either the receptacle I8 or cylinder 23 or the inner area of chamber 2. Since upon manual operation of finger lever 29 a force is exerted upon the fluid in cylinder 23, the amount of water injected may be controlled and also may be made to enter the steam chamber 2 in a fine stream of small diameter in a spurt or jet. Manifestly, upon the return or downward stroke of piston 24 responsive to spring 9|, the pump cylinder 23 will be replenished with an amount of fluid equal to the amount previously displaced, and the spring 3| returns the lever 29 to its nonpumping position. Upon operating the lever 29 the small quantity of water injected into steam chamber 2 is instantly converted to steam, in the manner of a flash boiler, due to the thinness of the cavity thereof as compared with its surface area which is adjacent the heating coils 5b, providing a heating area of large surface and crosssection as compared with the selective volume of water which may be introduced into the steam chamber 2 through the feed inlet 22 of relatively small lateral cross-section. As the steam pressure builds up it discharges through tube I2 of small lateral cross-section to actuate the aspirator, drawing material from receptacle I1 and discharging the mixture in a tine spray from nozzle I2.

Since the interior passageway of tube 2I is relatively small as shown at 22 and becomes heated through its connection with cylinder I, expansion of the steam from the water passing through its heated end would normally prevent free flow of the water therethrough, but by providing an expansion chamber at 33 this difficulty is entirely eliminated, since the back pressure or surge of the expansion is reflected back to the large volume of chamber 33.

In the embodiment of the invention shown in Fig. 2, the several parts are identical with those described, only the form of the flash boiler chamber 2 being changed. In this case the double walls of the chamber 2 are so positioned that the chamber is wider on one side as at 39 than on the opposite side as at 49. In other words, the inner wall of the chamber is eccentrically placed relative to the outer wall. By means of this arrangement any tendency of globules of water to form on the hot surface of the inner wall and travel around the same is obviated since the globules will be eilectually dispersed when they attempt to pass through the restricted portion of the chamber. Likewise, when the restricted portion of the chamber is at the bottom no opportunity is provided for water to collect, because the restricted passage forces intimate contact between the water and the heated inner wall.

The embodiment shown in Fig. 3 is similar to the one described except that the steam chamber is centrally located as at 4I in cylinder 42. 'I'he cylinder 42 is encased in a mica sheet 43 and this is enclosed by the heating unit 44 insulated by layers of insulating material as at 4l, the inlet to the chamber 4I being shown at 4l and the outlet in dotted lines at 41.

The embodiment shown in Fig. 4 is also similar to the embodiment shown in Fig, 1 except that the heater unit-steam chamber member is disposed vertically instead of horizontally and has the thermostat mounted on one end thereof as at 48.

In the modification of Fig. 5 there is disclosed a compact arrangement of parts incorporating the several features of the invention in a conveniently portable apparatus in which an electrical switch and water pump are accessibly located, and a safety feature is incorporated in the switch. In this modification, there is provided a supporting member 5I of any' suitable material, preferably of plastic electrically non-conducting type. The support member 5I may, in a sense, be termed a top casing and hand-grip, and is best made in two parts which flt snugly together in-facetoface contact ard are fixedly positioned relatively by screws or bolts 52, each part having grooves and channels formed therein to receive the conducting wires and conduit: hereafter described. The support member 5I has an opening 53 therethrough which forms a handle or handgrip portion. Depending from the support 5I is a casing 54 which may be removably attached to the lower skirt portion 5Ia of the support 5I by resilient snap buttons 55. The support member 5I is hollowed out at its bottom portion as at 5Ib to provide spacing to receive the upper ends of containers, one of such containers being the steam chamber or flash boiler generally indicated 56 which is mounted as at 56 to the supporting member 5I, and is disposed operatively between .a reservoir 51 for a supply of water or other suitable liquid for making steam and a flask 53 for liquid insecticide, soap, powder, or other material to be sprayed. The skirt portion of the support has suitably mounted therein at' each of its ends threaded cap members 59 and 68, each of which is provided with a packing gland, respectively 59a and 68B. To the cap 59 is threadedly and removably mounted the water reservoir 51 and to the cap 68 there is similarly mounted the flask 58. The center container 56 houses the ash boiler or steam chamber 6|.which comprises an elongated cylinder having an inner and outer wall relatively spaced and being closed at eachend. Qircumferentially of the outer wall of the steam chamber is a casing 62 lof suitable non-inflammable electrical insulating material, such as mica, and circumferentially of the insulating casing 62 are electrically conducting resistance heater elements 63 which are helically wound around the steam chamber 6I and are connected in an electrical circuit hereinafter described. Surrounding the steam chamber 6| on all of its sides is insulating packing material 64 which serves the double purpose of thoroughly insulating the heater element 63 externally and also retaining the heat `of, steam chamber 6|, for which latter purpose said insulation extends up into the hollow center of the steam cylinder but I leaving a suilcient space for a thermostat switch 65 which is mounted in said cylinder by means of a bracket 66 of electrical insulating material. It will be noted that in each of the Figs. 1, 5 and 6 a thermostat is positioned so as to be separated from the direct heat of the heating means and so as to be operative more directly responsive to the temperature of the steam chamber than to the temperature of the heating means. This is an important factor since it is the temperature of the boiler and not the temperature of the heating means which produces the flash of steam. For instance, if the thermostat is mounted so as to be directly affected by the temperature of the heating element or coil rather than by the temperature of the boiler, it results in the latent or retained heat of the heating element preventing the thermostat from snapping to make a contact until the temperature of the heating element ls reduced sufficiently, whereas, it is the temperature of the steam chamber of the boiler and not of the heating element which is critical in producing the flash steam for operating the apparatus. For that reason, the thermostat control is arranged where it snaps to complete the electri^y cal circuit and apply additional heat whenever the temperature of the steam chamber is reduced to the point at which a flash of steam V would not be effected by a .iet of additional water pumped into the boiler. The thermostat 65 comprises a well-known electrical conducting bimetal bar reactive to oscillation at its free end due to change of temperatures. At one end the thermostat bar 65 is xedly mounted on the bracket 66 by an electrical contact post 61 and havingits opposite free or oscillating end normally in contact with an electrical contact post 68 which is also mounted in bracket 66 and thereby insulated.. An electrical conduit extends from the contact post 68 and connects with the heating element 63, and through said element to one line 69 of an electrical current source. y'I'he other thermostat post 61 connects with an electrical conduit 18 leading to a switch 1| and being connectedthrou'gh said switch to the other line 12 in an electrical circuit. The switch 1| is operated by a lever 13 hingedly connected as at 14 to the hand grip portion of the supporting member 5|. The switch is normally maintained open by a, spring member 14 attached to a switch lever 15. When the apparatus is lifted by gripping the handle portion of member 5|, including the lever 13, the latter moves pivotally upwardly toward the under side of the hand grip, and the spring 14 is tensioned and the switch 1| is vclosed through the lever 15, and since the thermostat 65 is normally in contact with the -post 66, an electrical circuit is completed through the heater coil 63. If, however, the steam chamber becomes overheated, the thermostat will react to break the contact between itself and the post 68 and thus break the circuit until the temperature of steam chamber 6| is lowered sufilciently to permit the thermostat to again assume its normal position in contact with the post 68, whereupon the circuit is again closed. The reaction of the thermostat 65 is independent of the switch 1l and even though the switch 1| should remain closed the thermostat would serve to break the circuit when too high a temperature had been reached in the apparatus. This safety feature, generally known as a dead man switch, nds many advantages where the apparatus is employed in structures where it must meet iire insurance regulations, since even if the switch 1| should inadvertently fail to operate and break the circuit the thermostat would automatically do so. f

.The dead man switch also has an additional operative safety factor in that it comprises an associated assembly wherein the handle lever 13 automatically snaps the switch 1| into contacting relation when the device is lifted for operation by the operator and breaks the contact of the switch 1| by retraction of spring 14 when the hand grip of the device is released by the operator which ordinarily is when the operator sets the device down and discontinues the spraying operation.

Thus, regardless of whether or not there be a thermostat, an operator cannot go away from the device and inadvertently leave the switch in contacting relation. Fire hazard from such inadvertence is thus eliminated, in addition to eliminating the inconvenience of any necessity of manually turning on and turning oi an operating switch. V

The water reservoir 51 has a tube 16 extending through its cap 59 'and to adjacent the bottom of the reservoir. The tube 16 is adapted to receive a ow of water therethrough. The tube 16 connects with a pump assembly 11, and as herein exemplified, is formed of a suitable resilient rubber tubing 18 which is connected at one end to an inlet check valve 19 actuated to closed position by spring member which permits water to flow by suction into the pump but not to flow in the opposite direction. At the other end of the rubber tube pump 11 is an outlet check valve 8| which is similarly spring-operated as at 82 to permit water to ow by pressure from the pump 11 but not reversely thereinto. Connected to the outlet check valve 8| is a conduit 83 leading to and opening into the steam chamber 6|. The rubber tube pump 11 is operated on the wellknown suction and pressure principle by a force means consisting of lever 84 which may be pressed by the thumb of the operator when simultaneously grasping the handle portion 53 of the support 5|, and the switch lever 13. The

lever 84 is pivotally mounted at 85 so that pressure on the lever 84 actuates a at portion 86 of the lever for the purpose of deforming or depressing the resilient tube 18 of the pump, which action forces a relatively small spurt of water through the outlet valve 8| and tube 83 and invjects it into the steam chamber or flash boiler 8|. Upon release of the lever 84 the pump 11 renews its supply of water from the water-reservoir 51 through the conduit 16 and intake valve 19, responsive to the suction of resilient pump 11. As in Fig. l, likewise in Fig. 5, the pump cavity contains a relatively small amount of the fluid to be vaporized as compared with the fluid capacity of the source of fluid supply (receptacle 51), and the feed tube 83, and the outlet tube 88 are both relatively small in lateral cross-section as compared with the surface and cross-sectional areas of chamber 2; thus providing for feeding a relatively small selective amount of the vaporizable fluid at any one instant, and preferably injecting it as a spurt or jet responsive to force exerted on the rubber tube pump by lever 84, the chamber 2 providing an expansion chamber for the liquid thus vaporized. Obviously, when finger pressure is released from lever 84 the resiliency of rubber tube pump 11 acts as a resilient means similar to a spring to refill the pump for displaced water and returns the lever 84 to its normal non-pumping position for repeat of manual operation. Also connected to the flash boiler at the opening 81 is a tubular member 88 which has a spray nozzle 89 at its free end. Tubular member 88 and the spray nozzle are mounted by a suitable bracket 90, adjacent to the threaded cap 60 of the ilask 58. 'I'he flask 58 is provided with a tube 9| therein extending from a point adjacent its bottom through the cap thereof and having the opening at its outer end adjacent the spray nozzle of the tube 88, the latter being slightly resilientl so that it may be adjusted `with relation to the outlet of tube 9| by a rotatable eccentric 92 mounted in a lug 93 which is supported on the bracket 90. The steam chamber of flash boiler 6| being elongated and having its side walls spaced relatively close together provides a relatively long thin area for the reception of water through the tube 83. Since a large area of the flash boiler is exposed to the heating elements 63 as compared with the volumetric capacity of the steam chamber, the water received into the steam chamber is converted into the steam instantaneously, especially when the steam chamber is thoroughly heated as is the fact under practical operating conditions.

It is manifest that when the steam chamber or flash boiler 8| is properly heated to the predetermined temperature which is controlled by thermostat 85, the operator, having opened the switch 1| by means of the lever 13 gripped in his hand, may press with his thumb upon the lever 84 which, operating on the pump 11, injects a stream of water into the steam chamber 8| of the flash boiler wherein it is instantly turned to steam and the expansion thereof provides a pressure throlmh the tube 88 and the nozzle 89, thereby providing an aspirator to draw liquid from the flask 58, through the tube 9| and atomize it in a disperse system as a combined spray or mist of small globules of steam and the material from the flask 58. The resilient pump 11 may be made of any desirable size and capacity so that pressure may be exerted thereon for a considerable period continuously before all the water therein is injected into the flash boiler. In that manner of operation the continuity of spray may be maintained over a very considerable period of time. Or, on the other hand,-if

brief interval, the operator can likewise depress the lever 84 for whatever time the spray is desired.

In Fig. 6 the diagrammatic view illustrates the application of the invention to large spraying operations such as in orchards for spraying of trees or large areas of crops, and in which |0| is the reservoir for water, |02 is the flask for an insecticide or other material to be sprayed, and |03 is the flash boiler and steam chamber. Each of the foregoing elements may be of the same general construction as the similar elements in Fig. 5. However, since electrical current may be inaccessible for such roving operations over large out-door areas, a heater or burner element |04 is placed under the flash boiler for generation of steam therein. The heater |04 may be operated by oil as a fuel in the same manner as any standard and well known oil burner. A thermostat |05 mounted on the wall of the boiler operates through an electrical conduit |06, to operate ya solenoid |08 which actuates a valve |09 to control the flow of oil in conduit tube ||0, and thus regulate the flow of oil to burner |04, thereby regulating the heat applied to the flash boiler |03. 'I'he solenoid |08 is so arranged that it will not completely cut oil the flow of oil through the conduit ||,0, as it is not desired that the thermostat shall automatically completely extinguish the ame of burner |04, but the valve |09 may be manually manipulated to completely cut off the flow of' oil to extinguish the flame of the burner. Apump is provided to mechanically pump a supply of water from reservoir |0| to the steam chamber of flash boiler |03 through conduit ||2 and this pump has a throttle ||3 by which the pumping of water may be controlled by the operator. The pump may be driven by an internal combustion engine ||4 which also operates a generator ||5, the latter supplying electrical current to the solenoid |08 which operates` to regulate the valve |09.

Assuming the burner |04 to be burning and the flash boiler to be heated, the operator manually controls the pump'in operation by throttle |I3 during any desired period of spraying operation. The pump has the usual inlet andy outlet valves common to pumps, and when operated pumps water through conduit ||2, to the steam chamber of flash boiler |03 where it is instantly vaporized to steam which is exhausted through conduit ||6 to spray nozzle l I1 providing an aspirator in combination with the open end I I8 of tube I9 which extends-to a point adjacent the bottom of flask |02, thereby spraying the material in flask |02 by force of the exhausting stream and providing a spray of intimately commingled globules of prepared spraying mixture directly from the rethe spray is only desired for an instant or a very spective sources of liquid supply, I8 in Fig. 1, 51 in Fig. 2, or |0| in Fig. 3. This may be accomplished by merely eliminating a fluid material to be sprayed from the respective flasks |1,'58 or 02.v

The reference to the flash boiler as a cylindrical structure is intended to be generic to other forms in which a relative thin or narrowsteam chamber is provided, having a hollow or tubular central space or spaces.

vI claim: i

1. In a flash vaporizing apparatus having a handgrip supporting handle member and having means for feeding a vaporizable fluid and a discharge outlet for vaporized uid, a flash boiler vaporizing chamber having communication with of the flash boiler, said flash boiler having thermostatic control means operable responsive to the temperature of the boiler member and removed from the heat of the heating means whereby the thermostat is operable responsive to the temperature in the flash boiler for controlling the heating means, and said pump including a finger operable member accessible to the handle member` for manual manipulation by the same hand of an operator which supports the flash vaporizing apparatus by said handle.

2. In a flash vaporizing apparatus having a handgrip supporting handle member and having means for feeding vaporizable fluid and a discharge outlet for vaporized fluid, a flashboiler l vaporizing chamber having communication with the feed means and the discharge outlet, and providing an expansion chamber for the vaporizable fluid of large cross-section area as compared with the lateral transverse cross-sectional' area of the respective feed means and outlet, means for heating the flash boiler chamber, and a pump having a one-way flow valve and a force means operable intermittently on the feed means for intermittently feeding a selective quantity of vaporizable fluid to the chamber of the flash boiler, and said ash boiler having thermostatic control means operative responsive to the temperature of the boiler and removed from the heat i feed means and the discharge outlet and providing an expansion chamber for the ,vaporizable fluid of large cross-section area as compared with;

the lateral transverse cross-sectional area of the respective feed means and outlet, means for heating the flash boiler chamber, and a pump having a force means operable intermittently on the feed means for intermittently feeding a selective quantity 'o'f vaporizable fluid to the chamber of the flash boiler, said flash boiler having thermostatic control means operative responsive to the temperature of the boiler member and removed from the heat of the heating means whereby the thermostat is operable responsive to the temperature in the flash boiler for controlling the heating means, and said pump including means for returning the force means to a nonpumping position, the said pump including a finger operable member accessible to the handle member for manual manipulation by the same hand of an operator which supports the dash vaporizing apparatus by said handle.

4. In a portable flash vaporizing apparatus having a handgrip supporting handle, a flash boiler chamber providing an expansion chamber for a vaporizable fluid fed thereinto, said chamber having a discharge outlet for vaporized uid,

an electric resistance coil for heating the flash boiler chamber, thermostatic control means operative responsive to the temperature` of the boiler lmember and removed from the heat of the heating means whereby the thermostat is adapted for controlling the heating means re-' sponsive to temperature in the boiler, and a pump having a manually operable finger-press member adjacent said handle and having a force means operable intermittently on the feed means for intermittently feeding a slective quantity of vaporizing fluid to the chamber of the flash boiler, and said pump including means for reirning the force means to a non-pumping posi- 5. In a manually portable flash vaporizing apparatus, a flash boiler member having a vaporizing chamber provided with a discharge outlet for vaporized uid, feed means for intermittently injecting a vaporizable fluid into the boiler chamber, electric resistance coil means for heating the flash boiler chamber, thermostatic control means in the electric circuit of said coil, said thermostatic control means being operable for making and breaking the electric circuit of said coilresponsive to the temperature of the boiler chamber member and a handle member for manually supporting the apparatus, the said feed means including a pump provided with a finger-press member adjacent to the/said handle and having means to return the pump to a non-pumping position.

l6. In a manually portable flash vaporizing apparatus, a flash boiler member having a vaporizing chamber provided with a discharge outlet for vaporized fluid, feed means for intermittently injecting a vaporizable fluid into the boiler chamber, an electrical resistance coil closely adjacent exteriorly of a wall of the chamber, thermostatic control means in the circuit of said coil and operative responsive to the temperature of the boiler member for making and breaking the electric circuit through the coil, a handle member for manually suporting the apparatus, a lever substantially parallel with land adjacent to said handle for gripping thereof in unison with the handle, an electric switch operable by said lever, for making and breaking the electric circuit of 'the heating coil, the said means for feeding the a flash boiler vaporizing chamber having a discharge outlet for vaporized uid communicating with the discharge nozzle, an electrical resistance v the heating means whereby the heating means is controlled responsive to the temperature in the flash boiler chamber.

8. A portable iiash vaporizing spraying apparatus having a spray discharge nozzle, and having, in a portable unit, a portable support member having mounted thereon and portable therewith a flash boiler `vaporizing chamber provided with a discharge outlet for vaporized fluid communicating with the discharge nozzle, an electrical resistance means in an electrical circuit for heating the flash boiler chamber, a feed means for vaporizable fluid communicating with the boiler chamber adapted for feeding a selective quantity of vaporizable duid intermittently to the chamber of the flash boiler, and a thermostatically operated make and break means in the electric circuit of the said heating means, said make and break means being thermostatically operative responsive to the temperature of the fiashboiler member for making and breaking the electrical circuit through the heating means whereby the heating means is controlled responsive to the temperature of the ash boiler chamber.

JAMES A. TISCORNIA. 

